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arXiv · 1107.2695

Improving the efficiency of organic light emitting diodes by use of a diluted light-emitting layer

S. H. Mohan·K. Garre·N. Bhandari·M. Cahay
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Abstract

The use of a thin mixed layer consisting of an inert diluent material and a light emitting material between the hole-transport layer and electron-transport layer of organic light-emitting diodes leads to an increase in the external quantum efficiency. The efficiency improvement is highly dependent on the thickness of the diluted light-emitting layer and driving current. Significant improvement seen at low current densities is explained in terms of effective hole confinement by the mixed layer while a modest decreases in efficiency at higher current densities may be attributed to luminescence quenching at the hole-transport layer/inert diluents material interface. The phenomena are demonstrated with three different inert diluents materials. A maximum external quantum efficiency improvement of about 40% is found for a diluted light-emitting layer thickness between 40 {\AA} and 60 {\AA}.

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S. H. Mohan, K. Garre, N. Bhandari, M. Cahay. 2011-07-13. Improving the efficiency of organic light emitting diodes by use of a diluted light-emitting layer. https://arxiv.org/abs/1107.2695

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